EPR of Transition-Metal Ions in Microplasma Coatings on the Aluminum Alloy D16

The influence of microplasma oxidation (MPO) conditions on the creation of the Al2O3 coatings on aluminum alloy D16 was studied by the electron paramagnetic resonance (EPR) technique. Aluminum alloy D16 contains alloyed transition metals such as Cu, Mn, Fe, Ni, and Ti incorporated into the coating structure during MPO. EPR data on transition-metal ions allow estimating the appearance of a high-temperature phase of Al2O3 due to the difference in incorporation coefficients of transition-metal ions in low- and high-temperature Al2O3 phases of MPO coatings. These data show that no high-temperature Al2O3 phases were created during anodic MPO.